You can return the item to the merchant as you normally would. Some retailers will be able to process the refund to the device; however, some retailers may still require the plastic card to perform the refund.
In some cases, you may be required to provide the last four digits of the Digital Account Number. This can be found by tapping on the Wallet tile within the Fitbit app.
Fitbit Pay is a trademark of Fitbit Inc. in the U.S. and other countries.